I love Lea Salonga's rendition of more (but I think that's because of my Filipino bias). If I don't consider the needs of the film and the character, then my vote is Lea.
HOWEVER, if I were asked which one would be a better fit for the movie AND the character, I'd have to say Judy Kuhn, without even stopping to think about it. I do think Lea has the ability to sound tougher, but she is at her best with the sweet songs.
I like your imperturbable perspicacity.